The present invention relates, in general, to electronics, and more particularly, to methods of forming power conversion devices.
In the past, various methods and circuits were utilized to implement power conversion functions. One typical configuration, referred to as a buck converter, was used to regulate an output voltage that had a value that was less than an input voltage. The buck converter typically included a switching transistor that was controlled by a pulse width modulation controller or other similar controller. The switching transistor was enabled in a switching mode to supply power from the input voltage to the output as the output voltage decreased below a desired value. Another typical configuration, referred to as a boost converter, was used to regulate an output voltage that had a value that was greater than the input voltage. The boost converter also utilized a switching transistor that was operated in a switching mode to boost the value of the input voltage to the desired output voltage value. In some applications, a boost converter and a buck converter were connected together in series or in tandem to provide a more regulated output voltage than either the boost converter or buck converter could individually provide. The tandem coupled buck and boost converters operated the switching transistors similarly to the separate boost or buck converter. One problem with this tandem configuration was efficiency. With both converters processing power in the switching mode, the overall efficiency was the product of the two efficiencies, thus, the efficiency was lower than desired. The lower efficiency resulted in excess power dissipation and heat as well as increased operating costs.
Accordingly, it is desirable to have a power conversion method that has increased efficiency.
For simplicity and clarity of illustration, elements in the figures are not necessarily to scale, and the same reference numbers in different figures denote the same elements. Additionally, descriptions and details of well known steps and elements are omitted for simplicity of the description. As used herein current carrying electrode means an element of a device that carries current through the device such as a source or a drain of an MOS transistor or an emitter or a collector of a bipolar transistor, and a control electrode means an element of the device that controls current through the device such as a gate of an MOS transistor or a base of a bipolar transistor.